Reply To: pre_get_posts – order posts by two different meta_keys (ACF select field)

• beccayo

• June 3, 2017 at 11:36 pm

Thank you for your reply, John. I did find this post, but couldn’t figure out how to use this in pre_get_posts.

Here’s what I have tried, but of course it doesn’t work:

function exhibition_pre_get_posts( $query ) {
	
	// do not modify queries in the admin
	if( is_admin() ) {
		return $query;
	}
	
	if( isset($query->query_vars['post_type']) && $query->query_vars['post_type'] == 'exhibition' ) {
		$query = new WP_Query( array(
    'meta_query' => array(
        'relation' => 'AND',
        'year' => array(
            'key' => 'year',
        ),
        'month' => array(
            'key' => 'month',
            'compare' => 'EXISTS',
        ), 
    ),
    'orderby' => array(
        'year' => 'DESC',
        'month' => 'DESC',
    ) 
) );
	}

	// return
	return $query;
}

add_action('pre_get_posts', 'exhibition_pre_get_posts');

I’m sure this is a rookie mistake and a misunderstanding of the fundamentals – I’m still very much a beginner, I’m afraid!